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Targeted delivery and labeling of single living cells in heterogeneous cell populations are of great importance to understand the molecular biology and physiological functions of individual cells. However, it remains challenging to perfuse fluorescence markers into single living cells with high spatial and temporal resolution without interfering neighboring cells. Here, we report a single cell perfusion and fluorescence labeling strategy based on nanoscale glass nanopipettes. With the nanoscale tip hole of 100 nm, the use of nanopipettes allows special perfusion and high-resolution fluorescence labeling of different subcellular regions in single cells of interest. The dynamic of various fluorescent probes has been studied to exemplify the feasibility of nanopipette-dependent targeted delivery. According to experimental results, the cytoplasm labeling of Sulfo-Cyanine5 and fluorescein isothiocyanate is mainly based on the Brownian movement due to the dyes themselves and does not have a targeting ability, while the nucleus labeling of 4',6-diamidino-2-phenylindole (DAPI) is originated from the adsorption between DAPI and DNA in the nucleus. From the finite element simulation, the precise manipulation of intracellular delivery is realized by controlling the electro-osmotic flow inside the nanopipettes, and the different delivery modes between nontargeting dyes and nucleus-targeting dyes were compared, showcasing the valuable ability of nanopipette-based method for the analysis of specially defined subcellular regions and the potential applications for single cell surgery, subcellular manipulation, and gene delivery.

Surface-enhanced Raman spectroscopy (SERS) has been recognized as a promising analytical technique for its capability of providing molecular fingerprint information and avoiding interference of water. Nevertheless, direct SERS detection of complicated samples without pretreatment to achieve the high-efficiency identification and quantitation in a multiplexed way is still a challenge. In this study, a novel spectral extraction neural network (SENN) model was proposed for synchronous SERS detection of each component in mixed solutions using a demonstration sample containing diquat dibromide (DDM), methyl viologen dichloride (MVD), and tetramethylthiuram disulfide (TMTD). A SERS spectra dataset including 3600 spectra of DDM, MVD, TMTD, and their mixtures was first constructed to train the SENN model. After the training step, the cosine similarity of the SENN model can achieve 0.999, 0.997, and 0.994 for DDM, MVD, and TMTD, respectively, which means that the spectra extracted from the mixture are highly consistent with those collected by the SERS experiment of the corresponding pure samples. Furthermore, a convolutional neural network model for quantitative analysis is combined with the SENN, which can simultaneously and rapidly realize the qualitative and quantitative SERS analysis of mixture solutions with lower than 8.8% relative standard deviation. The result demonstrates that the proposed strategy has great potential in improving SERS analysis in environmental monitoring, food safety, and so on.

The endoplasmic reticulum (ER) is crucial for the regulation of multiple cellular processes, such as cellular responses to stress and protein synthesis, folding, and posttranslational modification. Nevertheless, monitoring ER physiological activity remains challenging due to the lack of powerful detection methods. Herein, we built a two-stage cascade recognition process to achieve dynamic visualization of ER stress in living cells based on a fluorescent carbon dot (CD) probe, which is synthesized by a facile one-pot hydrothermal method without additional modification. The fluorescent CD probe enables two-stage cascade ER recognition by first accumulating in the ER as the positively charged and lipophilic surface of the CD probe allows its fast crossing of multiple membrane barriers. Next, the CD probe can specifically anchor on the ER membrane via recognition between boronic acids and

H2O2 is an essential signaling molecule in living cells that can cause direct damage to lipids, proteins, and DNA, resulting in cell membrane rupture. However, current studies mostly focus on probe-based sensing of intracellular H2O2, and these methods usually require sophisticated probe synthesis and instruments. In particular, local H2O2 treatment induces cell membrane rupture, but the level of cell membrane destruction is unknown because the mechanical properties of the cell membrane are difficult to accurately determine. Therefore, highly sensitive and label-free methods are required to measure and reflect mechanical changes in the cell membrane. Here, using an ultrasmall quartz nanopipette with a tip diameter less than 90 nm as a nanosensor, label-free and noninvasive electrochemical single-cell measurement is achieved for real-time monitoring of cell membrane rupture under H2O2 treatment. By spatially controlling the nanopipette tip to precisely approach a specific location on the membrane of a single living cell, stable cyclic membrane oscillations are observed under a constant direct current voltage. Specifically, upon nanopipette advancement, the mechanical status of the cell membrane can be sensibly displayed by continuous current versus time traces. The electrical signals are collected and processed, ultimately revealing the mechanical properties of the cell membrane and the degree of cell apoptosis. This nanopipette-based nanosensor paves the way for developing a facile, label-free, and noninvasive strategy to assay the mechanical properties of the cell membrane during external stimulation at the single-cell level.

Reactivation of T-cell immunity by blocking the PD-1/PD-L1 immune checkpoint has been considered a promising strategy for cancer treatment. However, the recognition of PD-L1 by antibodies is usually suppressed due to the N-linked glycosylation of PD-L1. In this study, we present an effective PD-L1-blocking strategy based on a sialidase-conjugated "NanoNiche" to improve the antitumor effect via T-cell reactivation. Molecularly imprinted by PD-L1 N-glycans, NanoNiche can specifically recognize glycosylated PD-L1 on the tumor cell surface, thereby resulting in more efficient PD-L1 blockade. Moreover, sialidase modified on the surface of NanoNiche can selectively strip sialoglycans from tumor cells, enhancing immune cell infiltration. In vitro studies confirmed that NanoNiche can specifically bind with PD-L1 while also desialylate the tumor cell surface. The proliferation of PD-L1-positive MDA-MB-231 human breast cancer cells under T-cell killing was significantly inhibited after NanoNiche treatment. In vivo experiments in solid tumors show enhanced therapeutic efficacy. Thus, the NanoNiche-sialidase conjugate represents a promising approach for immune checkpoint blockade therapy.

In this study, we developed a deep convolution neural network (DCNN) model for predicting the optical properties of carbon dots (CDs), including spectral properties and fluorescence color under ultraviolet irradiation. These results demonstrate the powerful potential of DCNN for guiding the synthesis of CDs.

lncRNA, a type of non-coding RNA, plays an important role in the osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BM-MSCs). In this study, lncRNA and mRNA microarrays were performed to study the change of gene expression during osteogenic differentiation of BM-MSCs. We focused on Hedgehog interacting protein (HHIP), because HHIP mRNA and lncRNA HHIP-AS1 were gradually down-regulated on days 0, 7, and 14 during osteogenic differentiation. In addition, the gene codingBM-MSCs with over-expressed or silenced lncRNA HHIP-AS1 were constructed to explore the biological role of HHIP-AS1 in osteogenic differentiation. BM-MSCs were lysed to determine the alkaline phosphatase activity. FluorescenceOverexpression of lncRNA HHIP-AS1 increased HHIP expression, which suppressed Hedgehog signaling pathway, as indicated by the reduction of SMO, Gli1 and Gli2. The suppression of Hedgehog signal was associated with the inhibited osteogenesis. HHIP knockdown abolished the suppression of osteogenesis induced by lncRNA HHIP-AS1 overexpression. Through binding to HHIP mRNA, lncRNA HHIP-AS1 recruited ELAVL1 to HHIP mRNA, whereby increasing the mRNA stability and the protein level.This study revealed that down-regulation of HHIP due to lncRNA HHIP-AS1 reduction promoted the osteogenic differentiation of BM-MSCs though removing the suppression of Hedgehog signal.

The purpose of this study was to develop and validate an individualized nomogram to predict venous thromboembolism (VTE) risk in hospitalized postoperative breast cancer patients.A single-central retrospective and non-interventional trial.For model development, we used data from 4,755 breast cancer patients between 1 November 2016-30 June 2018 (3,310 patients in the development group and 1,445 in the validation group). Overall, 216 patients developed VTE (150 in development group and 66 in validation group). The model was validated by receiver operating characteristic curves and the calibration plot. The clinical utility of the model was determined through decision curve analysis.The individualized nomogram consisted of six clinical factors: age, body mass index, number of cardiovascular comorbidities, neoadjuvant chemotherapy, surgical treatment, hospital length of stay and two pre-operative biomarkers of Homocysteine and D-dimer. The model at the 3.9% optimal cut-off had the area under the curve of 0.854 (95% CI, 0.824-0.884) and 0.805 (95% CI, 0.740-0.870) in the development and validation groups. A p = 0.570 of the calibration test showed that the model was well-calibrated. The net benefit of the model was better between threshold probabilities of 5%-30% in decision curve analysis.The nomogram of VTE risk assessment, is applicable to hospitalized postoperative breast cancer patients. However, multi-central prospective studies are needed to improve and validate the model. Effectiveness and safety of thromboprophylaxis in high-risk patients are needed to demonstrate in interventional trials.This nomogram can be used in clinical to inform practice of physicians and nurses to predict the VTE probability and maybe direct personalized decision making for thromboprophylaxis in hospitalized postoperative breast cancer patients.目标: 本研究的目的是开发和验证个体化列线图,以预测乳腺癌术后住院患者静脉血栓栓塞(VTE)的风险。 设计: 单中心回顾性非干预试验。 方法: 对于模型开发,我们使用了2016年11月1日至2018年6月30日期间4755名乳腺癌患者的数据(发生组3310名,验证组1445名)。总体来说,216例患者发生了静脉血栓栓塞(发生组150例,验证组66例)。通过接收者工作特性曲线和标定曲线对模型进行验证。通过决策曲线分析确定模型的临床实用性。 结果: 个体化列线图由6个临床因素组成:年龄、体重指数、心血管共病数量、新辅助化疗、手术治疗、住院时间以及术前同型半胱氨酸和D-二聚体两个生物标志物。在开发组和验证组中,3.9%最优截止点的模型下面积为0.854(95%可信区间,0.824-0.884)和0.805(95%可信区间,0.740-0.870)。校准试验的p = 0.570 表明模型校准良好。在决策曲线分析中,阈值概率在5%-30%之间,模型的净效益较好。 结论: 静脉血栓栓塞风险评估列线图适用于乳腺癌术后住院患者。然而,需要多中心前瞻性研究来改进和验证该模型。高危患者血栓预防的有效性和安全性需要在干预试验中证明。 影响: 该列线图可用于临床指导医生和护士预测静脉血栓栓塞发生率,并可指导乳腺癌术后住院患者血栓预防的个性化决策。.

Commercial wrought Mg alloys normally contain low alloying contents to ensure good formability. In the present work, high-alloyed Mg-6Al-4Zn-xSn (x = 1, 2 and 3 wt.%, respectively) alloys were fabricated by extrusion. Hereinto, Sn was proven to play an effective contribution to simultaneous improvement in strength and ductility that are traditional trade-off features of synthetic materials. It was found that the average grain size of those alloys decreases significantly from ∼11 to ∼4 μm as a function of Sn contents increasing from 0 to 3 wt.%, while the amounts of Mg2Sn and Mg17Al12 particles continuously increase. More importantly, the addition of Sn leads to the transformation of dominated deformation modes from { 10 1 ¯ 2 } extension twinning (1 wt.%) to pyramidal slip (3 wt.%) during tensile tests along the extrusion direction at room temperature. The advantageous combination of ultimate tensile strength (∼366 MPa) and elongation (∼19 %) in Mg-6Al-4Zn-3Sn alloy is mainly attributed to the strong strain hardening ability induced by the enhanced activity of non-basal slip. This work could provide new opportunities for the development of high-alloyed wrought Mg alloys with promising mechanical properties.

Cancer-derived extracellular vesicles (EVs) have attracted considerable attention for clinical diagnosis. However, a limiting factor in current EV assays is the ability to detect various EV cancer biomarkers expressed at different locations. Here, we report a biomimetic multifunctional nanoplatform for multilayer imaging of cancer biomarkers from the EV surface to the interior without complex pretreatment. Constructed from polydopamine-wrapped gold nanoparticles modified with multiple functional molecules, this nanoplatform can capture EVs from complex samples and target different EV cancer biomarkers for imaging analysis at the single-vesicle level. Combined with 96-well plates, this assay can distinguish cancer cell-derived EVs from normal ones in a high-throughput manner. Using serum samples, EVs from hepatocellular carcinoma (HCC) patients can be distinguished from healthy controls. This convenient workflow represents a promising tool for EV-based cancer diagnosis.

Controlled self-assembly is a powerful strategy for building mesoscopic superstructures. However, the construction of high luminescence, millimeter-sized and spatially well-defined 3D rare earth (RE) material assemblies is a challenging objective. Apart from ligand sensitized luminescence of RE3+ ions, improving their luminescence efficiency by changing the symmetry of the coordination environment of RE3+ ions is a promising approach. In this work, we propose a facile “hot-node” growth strategy for the preparation of millimeter-sized high luminescence 3D RE micro-networks (RE-MNs) using citric acid (CA) as a ligand with weak absorption and mismatched energy levels of RE3+ ions. A unique assembly mechanism for RE-MNs is revealed, mainly including RE3+/CA coordination, high temperature-promoted disordered aggregation, “hot-node” formation, and the “hot-node” controlled production of MNs. Surprisingly, the luminescence efficiency of RE-MN assemblies is ∼102 times stronger than that of RE3+/CA complex precursors. Based on detailed photoluminescence (PL) spectra analysis, the significantly enhanced PL is directly attributed to the symmetry deviation induced transition (SDIT) effect. The formation of RE-MN assemblies results in the decrease of symmetry of the coordination environment of RE3+ ions and leads to the deviation of RE3+ from the center of inversion, which directly changes the originally Laporte-forbidden f–f transition to an allowed transition. Such facile and gram-scale synthesis technology enables the formation of high luminescence RE-MN assemblies with narrow bandwidth emission with promise for application in light emitting diodes (LEDs).

A total of 11 new (

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Vinylpyrazine compounds are widely present in foods, especially in hot-processed foods, as a class of flavor compounds; however, their formation mechanism in food systems is still unclear. Therefore, in this study, 2-vinylpyrazine and 2-vinyl-6-methylpyrazine were identified in the Maillard model reaction of D-glucose and glycine. The Maillard model reaction of glucose–glycine was constructed to explore the effects of reaction parameters on vinylpyrazines and the related products. The Maillard reaction of [U-13C6] glucose and glycine was established, and alkylpyrazines and formaldehyde were determined via isotope tracing technique as the precursors of vinylpyrazines. The formation of vinylpyrazines was verified by building a model reaction between alkylpyrazines and formaldehyde. The H/D exchange experiment confirmed that the active site of alkylpyrazines was on the methyl group, which was the reaction site for the condensation reaction of alkylpyrazines with formaldehyde. Results suggest that vinylpyrazines are formed by the condensation reaction of alkylpyrazines and formaldehyde.

A novel topology Halbach permanent magnet array is proposed and applied to the design of a printed circuit board (PCB) axial flux permanent magnet (AFPM) motor. Compared with the traditional coreless AFPM motor, this novel topology for a Halbach permanent magnet array PCB stator AFPM motor has larger air-gap magnetic flux density and air-gap flux per pole. The magnetic flux leakage is effectively reduced, and the air-gap magnetic density is close to the sine wave. Results of the finite element analysis and prototype experiments verify the feasibility and effectiveness of the novel Halbach permanent magnet array PCB stator motor. A reference basis and practical value for the design of the PCB AFPM motor are provided.

Here, we report a convenient, fast labeling strategy for the imaging of cell surface sialic acids (SAs, nine-carbon monosaccharides located at the terminals of cell surface sugar chains). This strategy is based on the synthesis of sticky, furry and fluorescent "wool-balls", which are wound into nanoclusters from p-benzoquinone/ethylenediamine polymer "wires". With abundant amino groups at the surface, the wool-balls can easily stick to the C-7 aldehyde group generated at the ends of periodate treated SAs in less than 30 min.

Here, we report a single cell glycan labeling strategy by combining nanoscale intracellular glass electrodes with bioorthogonal reaction. With the tip diameter less than 100 nm, the nanopipette electrode can be spatially controlled to inject artificial monosaccharides into single living cells with minimal invasion. The injection process can be precisely regulated by electroosmotic flow inside the nanopipette, and fluorescence labeling of sialic acid at single cell level is achieved.

2-Acetylthiazole possesses a nutty, cereal-like and popcorn-like aroma and a low odor threshold, and this compound has been identified in some processed foods, while the formation pathway of 2-acetylthiazole has not been clearly elucidated. Here, a model reaction of d-glucose and l-cysteine was constructed to investigate the formation pathway of 2-acetylthiazole. l-Cysteine, d-glucose and the corresponding intermediates, namely, dicarbonyl compounds (DCs), were involved in the formation of 2-acetylthiazole and detected by high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS), high-performance ion chromatography (HPIC) and HPLC, respectively. The carbon module labeling (CAMOLA) technique revealed that the C-4 and C-5 of 2-acetylthiazole were derived from the carbons of glucose. The potential of glyoxal, which is degraded by glucose, to form 2-acetylthiazole was revealed for the first time. A novel route to form 2-acetylthiazole by the reaction of glyoxal and methylglyoxal produced by d-glucose with H2S and NH3 produced by l-cysteine was proposed.

This study aimed to explore the function of miR-24 in hypoxia/reoxygenation (H/R) -induced cardiomyocyte injury.We constructed a cardiomyocyte model of H/R using the primary cardiomyocytes isolated from Sprague-Dawley rats. To explore the role of miR-24, cells were transfected with a miR-24 mimic or miR-24 inhibitor. The RNA expression levels of miR-24 and Mapk14 were determined using qRT-PCR. The proliferation and apoptosis of cells were determined using a CCK8 assay and a flow cytometer. The TargetScan website was used to predict the targets of miR-24. A dual-luciferase reporter gene assay was conducted to verify whether Mapk14 is indeed a target of miR-24. A Western blot was applied for protein detection.H/R exposure decreased the expression of miR-24 in rat cardiomyocytes. Transfection of the miR-24 mimic into cardiomyocytes reduced H/R-induced injury as evidenced by an increase in proliferation and a decrease in the apoptotic rate. By contrast, transfection of the miR-24 inhibitor aggravated H/R-induced injury. The expression of Bcl-2 was increased while the levels of Bax and Active-caspase 3 were reduced in the H/R+miR-24 mimic group compared to those in the H/R group. H/R+miR-24 inhibitor group showed the opposite results. Mapk14 was identified as a target of miR-24. The mRNA level of Mapk14 and its protein (p38 MAPK) level were negatively affected by miR-24. Furthermore, we discovered that depletion of Mapk14 reduced the promoting effect of the miR-24 inhibitor on cell apoptosis.Overall, our results illustrated that miR-24 could attenuate H/R-induced injury partly by regulating Mapk14.

Detecting cell-surface sialic acids (SAs) is essential for cancer research, as accumulating evidence indicates that SA overexpression is closely related to unusual biopathways, such as tumorigenesis. However, it remains challenging to detect and classify membrane SAs. Here, a highly efficient and convenient two-step tagging strategy is described for live-cell profiling of membrane sialic acids with fluorescence imaging and SERS labelling. The fluorescence of SA-linked dyes indicates the SA distribution, whereas the Raman signals recognize the SA-linked proteins marked by aptamer modified SERS probes. Using the tumor markers MUC-1 and TNC as the model proteins, SAs can be partitioned into distinct space domains via Flu/SERS information on living cell membrane. Importantly, we find that SAs are highly expressed near MUC-1 and TNC on the surface of cancer cells, with subtle differences existing among various carcinoma cell lines, enabling classification of various types of cells. Together, our strategy provides a robust and versatile platform for highly detailed analysis of cell surface saccharide profiles and that it has great potential for optical biosensing and molecular diagnosis.

The aim of the present paper is to investigate several third-order differential subordinations, differential superordination properties, and sandwich-type theorems of an integral operator Ws,bf(z) involving the Hurwitz–Lerch Zeta function. We make some applications of the operator Ws,bf(z) for meromorphic functions.

A multi-valued logic system is a promising alternative to traditional binary logic because it can reduce the complexity, power consumption, and area of circuit implementation. This article briefly summarizes the development of ternary logic and its advantages in digital logic circuits. The schemes, characteristics, and application of ternary logic circuits based on CMOS, CNTFET, memristor, and other devices and processes are reviewed in this paper, providing some reference for the further research and development of ternary logic circuits.

While the conventional two-dimensional (2D) culture protocol is well accepted for the culture of mesenchymal stem cells (MSCs), this method fails to recapitulate the in vivo native three-dimensional (3D) cellular microenvironment, and may result in phenotypic changes, and homing and migration capacity impairments. MSC preparation in 3D culture systems has been considered an attractive preparatory and delivery method recently. We seeded human umbilical cord-derived MSCs (hUCMSCs) in a 3D culture system with porcine acellular dermal matrix (PADM), and investigated the phenotypic changes, the expression changes of some important receptors, including Toll-like receptors (TLRs) and C-X-C chemokine receptor type 4 (CXCR4) when hUCMSCs were transferred from 2D to 3D systems, as well as the alterations in in vivo homing and migration potential. It was found that the percentage of CD105-positive cells decreased significantly, whereas that of CD34- and CD271-positive cells increased significantly in 3D culture, compared to that in 2D culture. The mRNA and protein expression levels of TLR2, TLR3, TLR4, TLR6, and CXCR4 in hUCMSCs were increased significantly upon culturing with PADM for 3 days, compared to the levels in 2D culture. The numbers of migratory 3D hUCMSCs in the heart, liver, spleen, and bone marrow were significantly greater than the numbers of 2D hUCMSCs, and the worst migration occurred in 3D + AMD3100 (CXCR4 antagonist) hUCMSCs. These results suggested that 3D culture of hUCMSCs with PADM could alter the phenotypic characteristics of hUCMSCs, increase their TLR and CXCR4 expression levels, and promote their migratory and homing capacity in which CXCR4 plays an important role.

Objective To evaluate the efficacy and safety of low-dose rituximab in the treatment of hematologic abnormalities in patients with connective tissue disease. Materials and methods A total of 13 patients with connective tissue disease who did not respond to prednisolone and multiple immunosuppressive agents, or their disease recurred after treatment, were given 100 mg of rituximab only combined with prednisolone once a week for 4 weeks. Then, the therapeutic effects and adverse reactions were respectively observed in the 13 patients. Results Rituximab showed good and rapid efficacy in the treatment of refractory thrombocytopenia and autoimmune hemolytic anemia caused by systemic lupus erythematosus, Sjogren's syndrome, and mixed connective tissue disease. Only 1 patient had urinary tract infection. During 24-month follow-up, disease recurred in 7 patients who still responded to azathioprine/Tripterygium wilfordii. Conclusion Low-dose rituximab has good efficacy and safety in the treatment of hematologic abnormalities in patients with connective tissue disease.

The vibration of a cell membrane plays a key role in the regulation of cell shape and the behavior of cells. However, most existing approaches for the measurement of cell vibration require either exogenous modification or sophisticated techniques, and the main challenge lies in developing methods that can monitor membrane vibration of living cells directly. Herein, a noninvasive strategy based on ultrasmall quartz nanopipettes is introduced. With a tip size of less than 100 nm, nanopipettes can be spatially controlled for precision targeting of a specific location on the membrane of single living cells. Surprisingly, by employing a constant voltage, stable cyclic oscillations are observed from the continuous current versus time traces. The time-domain current can be decomposed into two basic waves: the high-frequency one indicates the local membrane vibration driven by the electro-osmotic flow from the nanopipette, whereas the low-frequency one indicates the natural frequency of the whole cell. This provides a simple but reliable method to test local and global membrane vibration of single living cells simultaneously with little damage, which provides a tool for the quantification of drugs, disease, or mutations of the cell structure.

The dispersion solid-phase microextraction (DSPE) combined with dispersion liquid–liquid microextraction (DLLME) was developed as a rapid, simple and effective pretreatment method for the determination of flavor enhancers (maltol, ethyl maltol, vanillin, methyl vanillin, ethyl vanillin) of ready-to-eat seafood products (dried squid, baked squid, fried fish, steamed abalone). Under the optimized DSPE–DLLME method, the developed method exhibited low limits of quantitation (0.20–0.50 μg g−1) and excellent linearity (R2 ≥ 0.995). The recoveries of flavor enhancers in the actual samples were 83.7%–114.9%. Compared with traditional pretreatment methods, the developed DSPE–DLLME method was rapid (17 min) and easy to determine the flavor enhancers by high performance liquid chromatography with photodiode array detector (HPLC-PDA). In the actual samples, creamy compounds such as vanillin, methyl vanillin and ethyl vanillin were hardly found. However, the flavor compounds produced by thermal reactions such as maltol (except for dried squid 3) and ethyl maltol were present in all samples.